Presentation on theme: "Water pollution 2. Pure water -- tasteless, colorless, and odorless -- is often called the universal solvent Pure water -- tasteless, colorless, and odorless."— Presentation transcript:

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Pure water -- tasteless, colorless, and odorless -- is often called the universal solvent Pure water -- tasteless, colorless, and odorless -- is often called the universal solvent

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. "Dissolved solids" refer to any minerals, salts, metals, cations or anions dissolved in water. This includes anything present in water other than the pure water (H20) molecule and suspended solids. (Suspended solids are any particles/substances that are neither dissolved nor settled in the water, such as wood pulp.). "Dissolved solids" refer to any minerals, salts, metals, cations or anions dissolved in water. This includes anything present in water other than the pure water (H20) molecule and suspended solids. (Suspended solids are any particles/substances that are neither dissolved nor settled in the water, such as wood pulp.). In general, the total dissolved solids concentration is the sum of the cations (positively charged) and anions (negatively charged) ions in the water.. Parts per Million (ppm) is the weight-to-weight ratio of any ion to water.. In general, the total dissolved solids concentration is the sum of the cations (positively charged) and anions (negatively charged) ions in the water.. Parts per Million (ppm) is the weight-to-weight ratio of any ion to water.. Conductivity is usually about 100 times the total cations or anions expressed as equivalents. Total dissolved solids (TDS) in ppm usually ranges from 0.5 to 1.0 times the electrical conductivity. Conductivity is usually about 100 times the total cations or anions expressed as equivalents. Total dissolved solids (TDS) in ppm usually ranges from 0.5 to 1.0 times the electrical conductivity What Are Total Dissolved Solids - TDS?

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Some dissolved solids come from organic sources such as leaves, silt, plankton, and industrial waste and sewage. Some dissolved solids come from organic sources such as leaves, silt, plankton, and industrial waste and sewage. Dissolved solids also come from inorganic materials such as rocks and air that may contain calcium bicarbonate, nitrogen, iron phosphorous, sulfur, and other minerals. Dissolved solids also come from inorganic materials such as rocks and air that may contain calcium bicarbonate, nitrogen, iron phosphorous, sulfur, and other minerals. Many of these materials form salts, which are compounds that contain both a metal and a nonmetal. Salts usually dissolve in water forming ions. Ions are particles that have a positive or negative charge Where do Dissolved Solids come from?

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Why Should You Measure the TDS level in your Water? a maximum contamination level of 500mg/liter (500 parts per million (ppm)) for TDS.. When TDS levels exceed 1000mg/L it is generally considered unfit for human a maximum contamination level of 500mg/liter (500 parts per million (ppm)) for TDS.. When TDS levels exceed 1000mg/L it is generally considered unfit for human Most often, high levels of TDS are caused by the presence of potassium, chlorides and sodium. These ions have little or no short-term effects, but Most often, high levels of TDS are caused by the presence of potassium, chlorides and sodium. These ions have little or no short-term effects, but toxic ions toxic ionstoxic ionstoxic ions (cadmium, nitrate and others) may also be dissolved in the water. (cadmium, nitrate and others) may also be dissolved in the water.

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High TDS results in undesirable taste which could be salty, bitter, or metallic. It could also indicate the presence of toxic minerals High TDS results in undesirable taste which could be salty, bitter, or metallic. It could also indicate the presence of toxic minerals

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procedure Take an evaporating dish dry it and weigh it (w1) Filter the the water sample through whatmans paper (filtrate is as much clear as possible) The minimum sample volume should be 100ml (add deioised water to make up the volume if required) Evaporate the clear filtrate in dish in awater bath Heat at 105°c for 24hours Cool in dessicator and take the final weight(w2)

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Chloride (Cl) Chloride (Cl) is one of the major anions found in water and are generally combined with calcium, magnesium, or sodium. Since almost all chloride salts are highly soluble in water, the chloride content ranges from 10 to 100 mg/I is one of the major anions found in water and are generally combined with calcium, magnesium, or sodium. Since almost all chloride salts are highly soluble in water, the chloride content ranges from 10 to 100 mg/I

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Chloride itself in drinking water is generally not harmful to human beings but at high concentrations, the sodium associated with chloride can be of concern to people suffering from heart or kidney disease Chloride itself in drinking water is generally not harmful to human beings but at high concentrations, the sodium associated with chloride can be of concern to people suffering from heart or kidney disease

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procedure Add 50ml of water sample in a porcelian dish Add 50ml of water sample in a porcelian dish To this now add 1ml of potastium chromate indicator To this now add 1ml of potastium chromate indicator The indicator gives a yellow colour to the sample The indicator gives a yellow colour to the sample This is titrated against silver nitrate until brick red coloure developes This is titrated against silver nitrate until brick red coloure developes Note the amount of silver nitrate consumed Note the amount of silver nitrate consumed